Air pollution effects on your lungs, including lung cancer

Find out who is most at risk from air pollution, and how different types of air pollutants can affect your lungs

What is air pollution?

Air pollution is anything that makes the air more toxic and damaging to our health. Air pollution can affect all parts of our bodies, including the health of our lungs, heart, and brain.

Some people are more at risk and may be affected by pollution even on lower pollution days: 

  • Children are more at risk than adults because their lungs are still developing. They also breathe faster, which means they take in more polluted air. Being exposed to pollution as a child increases the risk of developing asthma and COPD as an adult.
  • Older people are more at risk, particularly if they have long-term lung conditions or heart disease. 
  • If you’re pregnant, pollution can affect your unborn baby. 

Air pollution and lung conditions

Air pollution harms us all, but it’s especially harmful if you have a lung condition.

  • Air pollution can irritate your airways and increase your lung symptoms.
  • Some types of air pollutants can get deep into the lungs and cause inflammation. 
  •  If you have asthma, air pollution can be a trigger.
  • When pollution levels are high, there are more admissions to hospital by people with lung conditions, including asthma and chronic obstructive pulmonary disease (COPD).
  • There is some evidence to suggest that air pollution could increase the risk of severe illness from COVID-19.

Can air pollution cause lung conditions?

Being exposed to air pollution over a long period of time can cause lung conditions, including asthma and chronic obstructive pulmonary disease (COPD).

If you’re exposed to high levels of pollution when you’re pregnant, whether you have asthma yourself or not, your baby could be more likely to develop asthma.

Air pollution also increases the risk of lung infections like bronchitis and pneumonia.

And there’s evidence that breathing in particulate matter (PM) plays a part in the development of lung cancer.

Pollution signs and symptoms 

If pollution is affecting you, you may notice that you: 

  • are coughing more
  • have difficulty breathing
  • are wheezing
  • have irritation in your nose and throat
  • are in pain when taking a breath
  • are more breathless when doing activity outdoors
  • find your lung symptoms are worse
  • are having asthma attacks or COPD flare-ups 
  • need to use your reliever inhaler more often.

Types of pollutants and how they affect your lungs

Particulate matter, nitrogen dioxide, ozone, and sulphur dioxide are particularly damaging types of air pollution.

Other natural sources of air pollution include volcanoes, pollen, sandstorms and soil.

Particulate matter (PM)

Particulate matter (PM) is made up of tiny pieces of solids or liquids in the air, such as dust, dirt, and smoke in the air.

  • High levels of PM are found close to manufacturing and industrial sites, building sites and quarries, and where fossil fuels are burned. 
  • Domestic wood burning, in wood burning stoves or open fires, is now the largest producer of particulate matter in the UK.
  • PM is higher on busy roads, especially roads with heavy vehicles like lorries, and when traffic is moving slowly.
  • Brake and tyre wear, and road dust all produce PM which means electric vehicles also contribute to PM.
  • PM levels go up in early November, around Bonfire Night. The smoke from fireworks and bonfires can create what’s known as ‘winter smog’ which can be worse on cold, still days.
  • PM can be produced naturally too. Volcanoes, sea spray, pollen and soil all add PM to the air.

Particulate matter is made up of particles of different sizes.

Large particles such as dust, soot, dirt or smoke are large or dark enough to be seen. These are large enough to be trapped by your nose.

The most damaging particles are the smaller ‘fine’ particles that you can’t see, known as PM10 and PM2.5, and the ultrafine particles.

Fine particulate matter harms people with lung conditions

  • PM10 particles can reach your airways.  
  • PM2.5 particles can reach the breathing sacs in your lungs.
  • Ultrafine particles can cross into your bloodstream. These particles can also carry toxic chemicals that are linked to cancer. 

Find out about levels of fine particulate matter around GP surgeries, hospitals, care homes and schools in your area with our map.

Nitrogen dioxide (NO2)

Nitrogen dioxide is a brown toxic gas in the air. Nitrogen dioxide levels are higher:

  • on busy roads, particularly when traffic is moving slowly, or where there are older, less efficient vehicles  
  • around industrial sites  like factories, and building sites 
  • where fossil fuels like coal and oil are burned.

High levels of NO2 can irritate your airways

High levels of NO2 can irritate the lining of your airways and make them more inflamed.

You’re more at risk from asthma attacks and COPD flare-ups when pollution levels are high.  

If you use a reliever (or rescue) inhaler, always carry it with you and use it as soon as you notice symptoms.

Ozone (O3)

Ozone is produced when sunlight combines with nitrogen dioxide, particulate matter, and other gases.

  • There are higher levels of ozone in the spring and summer, and in the afternoon.
  • There are lower levels of ozone in the winter, and in the mornings.
  • Ozone levels are often higher in the countryside than in the town.

High ozone levels can make it uncomfortable to breathe

High ozone levels can reduce your lung capacity (the amount of air your lungs can hold) and make it uncomfortable to breathe.

More people with lung conditions are admitted to hospital when ozone levels are high, and there’s a greater risk of getting pneumonia and bronchitis.

People with asthma may notice more symptoms and need to use their reliever inhaler more often. 

Sulphur dioxide (SO2)

Sulphur dioxide (SO2) is mainly produced by burning fuels like coal and oil. This includes domestic heating, factories, petrol refineries and building sites.  Sulphur dioxide can cause smog.

Sulphur dioxide can irritate the lining of your nose, throat and lungs

It can cause coughing and tightness of your chest, and make it harder to breathe.

When levels of SO2 are high, more people with asthma are admitted to hospital with asthma attacks.

Find out what you can do to lower your risk of air pollutants.

Get support

Call our Helpline for support with your condition. Get advice on your medicines, symptoms or travelling with a lung condition, or just call us to say hello.

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